External Interrupt / Event Controller (Exti); Introduction; Features; Figure 25. Exti Block Diagram - Holtek HT32F12345 User Manual

32-Bit Arm ® Cortex ® -M3 MCU
HT32F12345
11

External Interrupt / Event Controller (EXTI)

Introduction

The External Interrupt / Event Controller, EXTI, comprises 16 edge detectors which can generate
a wake-up event or interrupt requests independently. In interrupt mode there are five trigger types
which can be selected as the external interrupt trigger type, low level, high level, negative edge,
positive edge and both edges, selectable using the SRCnTYPE field in the EXTICFGRn (n = 0 ~
15) register. In the wake-up event mode, the wake-up event polarity can be configured by setting
the EXTInWPOL (n = 0 ~ 15) field in the EXTIWAKUPPOLR register. If the EVWUPIEN bit in
the EXTIWAKUPCR Register is set, the EVWUP interrupt can be generated when the associated
wake-up event occurs and the corresponding EXTI wake-up enable bit is set. Each EXTI line can
also be masked independently.
EXTI_PCLK
Debounce
16
EXTI 0
DBnCNT[15:0]
16
∫
EXTI 15
Deglitch

Figure 25. EXTI Block Diagram

Features

▄
Up to 16 EXTI lines with configurable trigger source and type
● All GPIO pins can be selected as EXTI trigger source
● Source trigger type includes high level, low level, negative edge, positive edge or both edge
▄
Individual interrupt enable, wakeup enable and status bits for each EXTI line
▄
Software interrupt trigger mode for each EXTI line
▄
Integrated deglitch filter for short pulse blocking
Rev. 1.10
High or Low level
Rising or Falling
or Both Edges
Edge/Level
Control
(SRCnTYPE[2:0])
16
Edge/Level
Detection
16
DBnEN
16
Polarity
Detection
Polarity
Control
(EXTInWPOL)
High or Low level
171 of 590
Software
Activate
(EXTInSC)
Interrupt Enable bits
& Interrupt Flags
16
EXTI Interrupt
16
16 Control &
Status
Event Enable bits
& Event Flags
EXTI Event
16
Control &
Status
16 External I/O Interrupt
(To NVIC control unit)
16
External I/O Event
(To NVIC control unit)
(To clock control unit)
November 28, 2018